1. Technical Field
The present disclosure relates to a carrier channel and a fabricating method thereof. More particularly, the present disclosure relates to a carrier channel with an element concentration gradient distribution and a fabricating method thereof.
2. Description of Related Art
In semiconductor devices, the carrier concentration in the active region would affect the performance of the device. How to control the carrier concentration and the carrier location precisely is a concerned issue in the semiconductor industry.
In the semiconductor industry, the thermal diffusion process and the ion implantation process have been widely used to control the carrier concentration and the carrier distribution. The thermal diffusion process promoted the carrier moving from high concentration region to low concentration region by using high temperature. But the thermal diffusion process consumes amount of time and energy, and it would increase the thermal budget and the production costs of the device significantly. Furthermore, the thermal diffusion process is only applied to the shallow area of the device.
Ion implantation process injects the carriers into the active region of the device by using an electric field to accelerate the carriers. The carrier distribution and the carrier location could be change by adjusting the electric field. Because the carriers acceleration by the electric field has strong energy, the carriers would damage the surface lattice of the device and generate form a lattice defect. Although the lattice defect can be repaired by executing an annealing process after the ion implantation process, but the annealing process increases the production costs of the device.
As foregoing mention, the conventional techniques should be improved by additional and time-consuming high temperature annealing process. However, the high temperature annealing process always increases the production costs.